The low-end storage marketplace is rife with an ever-expanding selection of incredibly cheap, feature-rich NAS devices. With support for RAID, hot-swap disks, CIFS file sharing, iSCSI block-level access, and a multitude of other useful features, these devices are a godsend for small businesses with surging storage needs. But if you try to use these devices for the same roles as their expensive enterprise-class cousins, disappointment may result.
The storage Swiss Army knife
A great example of this type of device is the QNAP TurboNAS line, so I'll use it as an example here. To be sure, the marketplace is packed with offerings from the likes of EMC's Iomega, D-Link, Netgear, and numerous others -- many of the points I make here apply equally to these devices.
The QNAP TurboNAS line is available in a wide selection of two- to eight-disk enclosures including both table-top and rack-mount form factors. The items ship without the required SATA disks, so the choice of drive is up to the end-user, making them very flexible in terms of capacity.
Using a Linux-based operating system, they support a cornucopia of features that even enterprise-grade devices rarely provide. These include the ability to offer files via any combination of CIFS, NFS, FTP, and HTTP, while also supporting multipath iSCSI block-level access. In addition, they support volume-level disk encryption; a full range of popular RAID types, including RAID6; and online RAID expansion, which makes it easy to upgrade your disks. Many of them are even approved for use with Citrix XenServer, Microsoft Hyper-V, and VMware vSphere in iSCSI-based clustering environments.